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P Yorio - One of the best experts on this subject based on the ideXlab platform.
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Using Morphometry and Molecular Markers for Sexing South American, Cayenne and Royal Terns Breeding in Patagonia, Argentina
Waterbirds, 2014Co-Authors: Nora Lisnizer, P Yorio, Leonardo Cotichelli, Néstor G. Basso, Alejandro GattoAbstract:Abstract. The first information on the morphometry and sexual size dimorphism of the sympatric South American (Sterna hirundinacea), Cayenne (Thalasseus sandvicensis eurygnathus) and Royal (T. maximus maximus) terns from the Patagonia region in Argentina is provided, and a discriminant analysis to sex the three species is used. Morphological characters were obtained from South American Terns (n = 83), Cayenne Terns (n = 63) and Royal Terns (n = 20). All species were sexed using polymerase chain reaction-based molecular techniques. Sexes in the three tern species were only slightly dimorphic in size. Male Cayenne and South American terns were significantly larger than females in bill length, bill depth and head length. Royal Terns, in contrast, showed a high overlap in most morphological measurements, with head length being the only measurement that differed significantly between sexes. Head length correctly sexed 89% of South American Terns and 75% of Royal Terns, while a function including bill depth and...
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provisioning of mates and chicks by Cayenne and royal terns resource partitioning in northern patagonia argentina
Emu, 2009Co-Authors: Alejandro Gatto, P YorioAbstract:Cayenne (Thalasseus sandvicensis eurygnathus) and Royal Terns (Thalasseus maximus) breed in mixed colonies in Argentina. This paper presents the first detailed information on their breeding diet and assesses differences and overlap between species in the type and size of prey. During 2004 and 2005, observations of prey delivered to mates and chicks were carried out at Punta Leon, Patagonia. The diet of Cayenne and Royal Terns comprised nine and 10 prey species respectively. Fish comprised >99% of the prey of both species of tern in the two study years. Both species had a fairly specialised diet based on pelagic schooling fish, mostly Argentine Anchovy (Engraulis anchoita) and two species of silversides (Odontesthes spp.). Despite observed overlap in trophic resources, our results showed that Argentine Anchovy was the main prey for Royal Terns, whereas the two species of silversides together with Anchovy comprised the bulk of the diet for Cayenne Terns. Fish delivered by Cayenne Terns were significantly smaller than those by Royal Terns. Results suggested that both type and size of prey may be important factors permitting food partitioning between the two species of tern during the breeding season.
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population status of royal and Cayenne terns breeding in argentina and brazil
Waterbirds, 2009Co-Authors: P YorioAbstract:Abstract In South America, Royal Terns (Thalasseus maximus maximus) and Cayenne Terns (Thalasseus sandvicensis eurygnathus) breed mostly in Argentina and Brazil. Royal Terns have been recorded in at least 22 locations (six in Brazil and 14 in Argentina). Cayenne Terns have been recorded in at least 38 locations (15 in Brazil and 23 in Argentina). At 15 locations, mostly located in Argentina, Royal and Cayenne terns breed in association, often with their nests intermingled. Total population size for Royal Terns was estimated in at least 750 pairs in Brazil and less than 5000 in Argentina, while that of Cayenne Tern was estimated in at least 8000 pairs in Brazil and less than 10000 in Argentina. However, lack of counts at some coastal sectors and changes among breeding sites between seasons preclude an accurate estimation of total population size for both species and make spatial management challenging. Main threats faced by their populations in both countries are human disturbance, fisheries, egging, and e...
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predation by kelp gulls larus dominicanus at a mixed species colony of royal terns sterna maxima and Cayenne terns sterna eurygnatha in patagonia
Ibis, 1997Co-Authors: P Yorio, F QuintanaAbstract:We studied the predator-prey interaction between Kelp Gulls Larus dominicanus and Royal Terns Sterna maxima and Cayenne Terns Sterna eurygnatha at Punta Leon, Argentina, from 1990 to 1992. Kelp Gulls were the main predator of tern eggs in all 3 years, accounting for 99% of observed predations (n = 454). A total of 99% of predations occurred on peripheral tern nests. Total predation rate on both tern species was highest in 1990 and varied significantly between years, with between 0.01 and 0.03 cases of predation per hour. Predation rates in all years were significantly higher on Cayenne than on Royal Terns probably because the latter were significantly more aggressive towards gulls than were Cayenne Terns. Royal and Cayenne Terns displayed aggressively towards gulls at least once in 64% and 10% of the observation periods, respectively. Defence behaviour, such as attacking and chasing the predator, was used more frequently by Royal than Cayenne Terns (13.2% v 3.6%). Predation on tern eggs was restricted to only a few Kelp Gulls which nested close to the tern colony periphery, and 50% of the eggs that were stolen were taken by only two pairs during 1991 and 47% by three pairs in 1992. This suggests that the current expansion of the Kelp Gull numbers at Punta Leon might not necessarily result in a proportional increase in predation rate on both tern species. Stealing eggs from the ground was more successful than from the air (77% v 17%). The nesting strategy shown by Royal and Cayenne Terns at Punta Leon appears to be an important factor which reduced the impact on their breeding success of high potential predation pressure by gulls.
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Predation by Kelp Gulls Larus dominicanus at a mixed‐species colony of Royal Terns Sterna maxima and Cayenne Terns Sterna eurygnatha in Patagonia
Ibis, 1997Co-Authors: P Yorio, F QuintanaAbstract:We studied the predator-prey interaction between Kelp Gulls Larus dominicanus and Royal Terns Sterna maxima and Cayenne Terns Sterna eurygnatha at Punta Leon, Argentina, from 1990 to 1992. Kelp Gulls were the main predator of tern eggs in all 3 years, accounting for 99% of observed predations (n = 454). A total of 99% of predations occurred on peripheral tern nests. Total predation rate on both tern species was highest in 1990 and varied significantly between years, with between 0.01 and 0.03 cases of predation per hour. Predation rates in all years were significantly higher on Cayenne than on Royal Terns probably because the latter were significantly more aggressive towards gulls than were Cayenne Terns. Royal and Cayenne Terns displayed aggressively towards gulls at least once in 64% and 10% of the observation periods, respectively. Defence behaviour, such as attacking and chasing the predator, was used more frequently by Royal than Cayenne Terns (13.2% v 3.6%). Predation on tern eggs was restricted to only a few Kelp Gulls which nested close to the tern colony periphery, and 50% of the eggs that were stolen were taken by only two pairs during 1991 and 47% by three pairs in 1992. This suggests that the current expansion of the Kelp Gull numbers at Punta Leon might not necessarily result in a proportional increase in predation rate on both tern species. Stealing eggs from the ground was more successful than from the air (77% v 17%). The nesting strategy shown by Royal and Cayenne Terns at Punta Leon appears to be an important factor which reduced the impact on their breeding success of high potential predation pressure by gulls.
F Quintana - One of the best experts on this subject based on the ideXlab platform.
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Predation by Kelp Gulls Larus dominicanus at a mixed‐species colony of Royal Terns Sterna maxima and Cayenne Terns Sterna eurygnatha in Patagonia
Ibis, 1997Co-Authors: P Yorio, F QuintanaAbstract:We studied the predator-prey interaction between Kelp Gulls Larus dominicanus and Royal Terns Sterna maxima and Cayenne Terns Sterna eurygnatha at Punta Leon, Argentina, from 1990 to 1992. Kelp Gulls were the main predator of tern eggs in all 3 years, accounting for 99% of observed predations (n = 454). A total of 99% of predations occurred on peripheral tern nests. Total predation rate on both tern species was highest in 1990 and varied significantly between years, with between 0.01 and 0.03 cases of predation per hour. Predation rates in all years were significantly higher on Cayenne than on Royal Terns probably because the latter were significantly more aggressive towards gulls than were Cayenne Terns. Royal and Cayenne Terns displayed aggressively towards gulls at least once in 64% and 10% of the observation periods, respectively. Defence behaviour, such as attacking and chasing the predator, was used more frequently by Royal than Cayenne Terns (13.2% v 3.6%). Predation on tern eggs was restricted to only a few Kelp Gulls which nested close to the tern colony periphery, and 50% of the eggs that were stolen were taken by only two pairs during 1991 and 47% by three pairs in 1992. This suggests that the current expansion of the Kelp Gull numbers at Punta Leon might not necessarily result in a proportional increase in predation rate on both tern species. Stealing eggs from the ground was more successful than from the air (77% v 17%). The nesting strategy shown by Royal and Cayenne Terns at Punta Leon appears to be an important factor which reduced the impact on their breeding success of high potential predation pressure by gulls.
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predation by kelp gulls larus dominicanus at a mixed species colony of royal terns sterna maxima and Cayenne terns sterna eurygnatha in patagonia
Ibis, 1997Co-Authors: P Yorio, F QuintanaAbstract:We studied the predator-prey interaction between Kelp Gulls Larus dominicanus and Royal Terns Sterna maxima and Cayenne Terns Sterna eurygnatha at Punta Leon, Argentina, from 1990 to 1992. Kelp Gulls were the main predator of tern eggs in all 3 years, accounting for 99% of observed predations (n = 454). A total of 99% of predations occurred on peripheral tern nests. Total predation rate on both tern species was highest in 1990 and varied significantly between years, with between 0.01 and 0.03 cases of predation per hour. Predation rates in all years were significantly higher on Cayenne than on Royal Terns probably because the latter were significantly more aggressive towards gulls than were Cayenne Terns. Royal and Cayenne Terns displayed aggressively towards gulls at least once in 64% and 10% of the observation periods, respectively. Defence behaviour, such as attacking and chasing the predator, was used more frequently by Royal than Cayenne Terns (13.2% v 3.6%). Predation on tern eggs was restricted to only a few Kelp Gulls which nested close to the tern colony periphery, and 50% of the eggs that were stolen were taken by only two pairs during 1991 and 47% by three pairs in 1992. This suggests that the current expansion of the Kelp Gull numbers at Punta Leon might not necessarily result in a proportional increase in predation rate on both tern species. Stealing eggs from the ground was more successful than from the air (77% v 17%). The nesting strategy shown by Royal and Cayenne Terns at Punta Leon appears to be an important factor which reduced the impact on their breeding success of high potential predation pressure by gulls.
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breeding biology of royal and Cayenne terns at a mixed species colony in patagonia
The Wilson Journal of Ornithology, 1997Co-Authors: F Quintana, P YorioAbstract:-We studied the breeding biology of Royal (Sterna maxima) and Cayenne terns (S. eurvgnatha) at Punta Le6n, Patagonia, during 1989-93. In all years, both species bred in a single colony with their nests intermingled. Colony size varied between 1,150 and 1,830 pairs. Colony formation occurred during the first or second week of October. Nesting densities were relatively high (9.8 to 1 1. I nests/m2). Both species started to lay eggs during the second and third week of October in all years. During 1993, clutch size for Royal and Cayenne terns was 1.3 + 0.5 and 1.1 + 0.3, respectively. The length of the incubation period was 25.7 t 0.9 and 29.1 + 3 days for Royal and Cayenne terns, respectively. During 1993, hatching success was 0.72 + 0.34 and 0.68 + 0.42 chicks per nest for Royal and Cayenne terns, respectively. Egg losses (45.3%) were mainly from predation. First-hatched chicks were observed during mid November. Chick survival to 10 days of age was 90% and 66.7% for Royal and Cayenne terns, respectively. At approximately 20 days of age, some tern chicks started to abandon the colony to form creches at the beach. Royal and Cayenne terns generally fed out of sight from the colony and preyed upon the same species, including Odontestes spp., Stromateus brasiliensis, Entgraulis ancuhoita, and Sprattus fueguensis. Received 16 Jan. 1997. accepted 3 June 1997. Royal (Sterna maxima) and Cayenne (S. eurygnatha) terns are two widely distributed species. Royal Terns breed from eastern North America to Patagonia (Escalante 1985, Yorio and Harris, in press) while Cayenne Terns, considered by some authors as a race or color morph of the Sandwich Tern (S. sandvicensis) (Buckley and Buckley 1984, Gochfeld et al. 1994), breed from the southern Caribbean to Patagonia (Olsen and Larsson 1995, Yorio and Harris, in press). In Argentina, both species breed at a few locations on the Patagonian coast (Zapata 1965, Korschenewski 1969, Daciuk 1972, 1976, Yorio et al. 1994). As in other regions (Bent 1921, Ansingh et al. 1960, Buckley and Buckley 1972a, Blus et al. 1979, Antas 1991), Patagonian Royal and Cayenne terns nest with each other or in association with other tern species (Zapata 1965, Daciuk 1973, Yorio and Harris, in press). On occasion, Royal and Cayenne terns breed in a single colony with their nests intermingled (Korschenewski 1969, Yorio et al. 1994). Like other species of the crested tern group, Royal and Cayenne terns have natural history traits distinguishing them from other tern species. In I Centro Nacional Patag6nico, CONICET, Blvd. Brown s/n 9120, Puerto Madryn, Chubut, Argentina. 2 Wildlife Conservation Society, New York, New York 10460.
Alejandro Gatto - One of the best experts on this subject based on the ideXlab platform.
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Using Morphometry and Molecular Markers for Sexing South American, Cayenne and Royal Terns Breeding in Patagonia, Argentina
Waterbirds, 2014Co-Authors: Nora Lisnizer, P Yorio, Leonardo Cotichelli, Néstor G. Basso, Alejandro GattoAbstract:Abstract. The first information on the morphometry and sexual size dimorphism of the sympatric South American (Sterna hirundinacea), Cayenne (Thalasseus sandvicensis eurygnathus) and Royal (T. maximus maximus) terns from the Patagonia region in Argentina is provided, and a discriminant analysis to sex the three species is used. Morphological characters were obtained from South American Terns (n = 83), Cayenne Terns (n = 63) and Royal Terns (n = 20). All species were sexed using polymerase chain reaction-based molecular techniques. Sexes in the three tern species were only slightly dimorphic in size. Male Cayenne and South American terns were significantly larger than females in bill length, bill depth and head length. Royal Terns, in contrast, showed a high overlap in most morphological measurements, with head length being the only measurement that differed significantly between sexes. Head length correctly sexed 89% of South American Terns and 75% of Royal Terns, while a function including bill depth and...
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provisioning of mates and chicks by Cayenne and royal terns resource partitioning in northern patagonia argentina
Emu, 2009Co-Authors: Alejandro Gatto, P YorioAbstract:Cayenne (Thalasseus sandvicensis eurygnathus) and Royal Terns (Thalasseus maximus) breed in mixed colonies in Argentina. This paper presents the first detailed information on their breeding diet and assesses differences and overlap between species in the type and size of prey. During 2004 and 2005, observations of prey delivered to mates and chicks were carried out at Punta Leon, Patagonia. The diet of Cayenne and Royal Terns comprised nine and 10 prey species respectively. Fish comprised >99% of the prey of both species of tern in the two study years. Both species had a fairly specialised diet based on pelagic schooling fish, mostly Argentine Anchovy (Engraulis anchoita) and two species of silversides (Odontesthes spp.). Despite observed overlap in trophic resources, our results showed that Argentine Anchovy was the main prey for Royal Terns, whereas the two species of silversides together with Anchovy comprised the bulk of the diet for Cayenne Terns. Fish delivered by Cayenne Terns were significantly smaller than those by Royal Terns. Results suggested that both type and size of prey may be important factors permitting food partitioning between the two species of tern during the breeding season.
Didier Raoult - One of the best experts on this subject based on the ideXlab platform.
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Three-toed sloth as putative reservoir of Coxiella burnetii, Cayenne, French Guiana.
Emerging Infectious Diseases, 2014Co-Authors: Bernard Davoust, Jean-lou Marié, Vincent Pommier De Santi, Jean Michel Berenger, Sophie Edouard, Didier RaoultAbstract:To the Editor: Q fever is an emerging zoonosis and a major public health concern in French Guiana, a French overseas region located on the northeastern coast of South America (1,2). Most cases occur in the city of Cayenne (3), specifically in the suburbs, where houses are near wooded hills (4). Genotyping performed by using multispacer sequence typing showed that MST17, a unique genotype of C. burnetii, circulates in Cayenne and is responsible for epidemics of Q fever (5). C. burnetii transmission peaks during the rainy season, and the incidence of Q fever usually increases 1–3 months later (6). The animal reservoir of C. burnetii in French Guiana is unknown; previous studies have excluded domestic ruminants, which are known to be C. burnetii reservoirs elsewhere in the world (6). Four serologic surveys showed few C. burnetii–positive opossums, dogs, rodents (Proechimys spp.), bovines, or birds in French Guiana (7). In 2013, using real-time PCR (qPCR) analysis of vaginal swab samples, we showed that 6/158 (3.8%) dogs from Cayenne and 0/206 bats from the coastal area of French Guiana were positive for C. burnetii (cycle threshold [Ct]
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three toed sloth as putative reservoir of coxiella burnetii Cayenne french guiana
Emerging Infectious Diseases, 2014Co-Authors: Bernard Davoust, Jean-lou Marié, Vincent Pommier De Santi, Jean Michel Berenger, Sophie Edouard, Didier RaoultAbstract:To the Editor: Q fever is an emerging zoonosis and a major public health concern in French Guiana, a French overseas region located on the northeastern coast of South America (1,2). Most cases occur in the city of Cayenne (3), specifically in the suburbs, where houses are near wooded hills (4). Genotyping performed by using multispacer sequence typing showed that MST17, a unique genotype of C. burnetii, circulates in Cayenne and is responsible for epidemics of Q fever (5). C. burnetii transmission peaks during the rainy season, and the incidence of Q fever usually increases 1–3 months later (6). The animal reservoir of C. burnetii in French Guiana is unknown; previous studies have excluded domestic ruminants, which are known to be C. burnetii reservoirs elsewhere in the world (6). Four serologic surveys showed few C. burnetii–positive opossums, dogs, rodents (Proechimys spp.), bovines, or birds in French Guiana (7). In 2013, using real-time PCR (qPCR) analysis of vaginal swab samples, we showed that 6/158 (3.8%) dogs from Cayenne and 0/206 bats from the coastal area of French Guiana were positive for C. burnetii (cycle threshold [Ct]<35). One of the positive samples was identified as genotype MST17 (5). A case–control study among humans identified several risk factors for Q fever, including living near a forest and the presence of wild animals near the house (6). During January–April 2013, a Q fever outbreak occurred in Tiger Camp, a military residential area located at the top of a wooded hill in Cayenne. Vaginal swab samples were collected from animals living in the area (13 goats, 8 sheep, 7 bats, 34 birds, 2 opossums, 4 iguanas, and 17 geckos); all samples were negative for C. burnetii by qPCR. In addition, serologic tests for C. burnetii were negative for samples from all 37 small ruminants maintained near the outbreak area. In January 2014, a dead (accidental death) female 3-toed sloth (Bradypus tridactylus) (Figure, panel A) was found on the road near the residence of a Q fever patient. We retrieved the sloth and collected feces, spleen, liver, kidney, lung, and uterus samples and a vaginal swab sample. A total of 16 ticks were removed from the sloth and stored in 70% alcohol. Figure Putative reservoir of Coxiella burnetii in Cayenne, French Guiana A) A 3-toed sloth (Bradypus tridactylus) in its natural habitat in Tiger Camp, a military residential area located at the top of a wooded hill in Cayenne, French Guiana (photograph by S. ... DNA was extracted from the feces, organs, and ticks by using the BioRobot EZ1 Workstation (QIAGEN, Courtaboeuf, France). qPCR targeting the repeated insertion sequence IS1111 was performed by using a CFX96 Touch Real-Time PCR Detection System (Bio-Rad, Marne la Coquette, France) as described (8). We confirmed all positive results by performing a second qPCR targeting the IS30a repeated sequence. DNA samples with Ct values <35 in both assays were considered positive for C. burnetii. A standard calibration curve quantifying the target IS1111 was generated by using 10-fold serial dilutions of C. burnetii Nine Mile strain. The number of IS1111 intergenic sequences found in the genome of strain C. burnetii MST17 was identical to that for the Nine Mile strain (F. D’Amato, unpub. data); thus, the qPCR that we used was valid for quantifying the number of C. burnetii MST17 IS1111 copies/mL in samples we collected (5). qPCR analysis showed that the feces were highly positive for C. burnetii; the sample had a low Ct value of 23, corresponding to 7 log10 DNA copies/mL (9). The spleen was also positive for C. burnetii; the Ct value was 34, corresponding to 3.6 log10 DNA copies/mL. Results for the other samples were negative. Using morphologic criteria, we identified all 16 ticks collected from the sloth as Amblyomma geayi (Figure, panel B). We performed C. burnetii–specific qPCR on the ticks; 14 (88%) were positive. We genotyped C. burnetii–positive DNA from the feces and from 6 of the 16 ticks by using multispacer sequence typing as described (5). All samples were identified as MST17, the unique genotype circulating in Cayenne (5). After obtaining the laboratory results, we confirmed that a local group in charge of the collection and treatment of injured animals usually released rehabilitated 3-toed sloths into Tiger Camp. Residents of Tiger Camp regularly observed and came into contact with the sloths, and ticks were frequently observed on the fur of the animals. Furthermore, 3 Q fever patients from Cayenne reported contact with sloths. Feces from the sloth in this study were highly infectious for C. burnetii. Because sloths live in tall trees and can shed this bacterium in their feces, human contamination might occur through inhalation of infectious aerosols from feces. The high prevalence of C. burnetii infection in ticks also suggests possible transmission through tick bites or from aerosols of tick feces that have been deposited on the skin of animal hosts; such feces can be extremely rich in bacteria and highly infectious (10). In this 2013 outbreak of Q fever, epidemiologic studies led to the identification of 3-toed sloths as a putative source of C. burnetii infection. Further investigations are needed to confirm the role of sloths as a reservoir for C. burnetii in French Guiana and to implement efficient measures to prevent transmission to humans.
Damiani Panatta - One of the best experts on this subject based on the ideXlab platform.
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Seasonal occurrence of Common Sterna hirundo and 'Cayenne' Terns S. sandvicensis eurygnathus in a tropical estuarine complex of northeast Brazil
2020Co-Authors: Rua Mário, Damiani PanattaAbstract:This year-long study (October 2002–September 2003) documented the seasonal occurrence of Common Terns Sterna hirundo and ‘Cayenne Terns’ S. sandvicensis eurygnathus at the Coroa do Aviao, a barrier islet located in an estuarine complex of the State of Pernambuco in northeast Brazil. Common Terns were present in the area almost all year round, except in December, February and March, with peak abundance in May–July. The islet is used by Common Terns as a stopover area during migration to and from their main wintering grounds in southern South America. ‘Cayenne Terns’ occurred mainly from August to October, being absent from December to April. In Brazil the ‘Cayenne Tern’ breeds from April to October and most birds at the islet were likely to have been individuals dispersing from colonies in southeast Brazil.
